Redundant internet

[mahmoodmkl]

Hi guys

I have dual internet connection from the same ISP.I want the secondry connection to take over if the primary connection fails.How can i do it.

Please help.

Thanks

Mahmood

[mohammedmahmoud]

Hi Mahmood,

What is the routing protocol you are using ?

If static/default you can just use floating static routes (for the upload 2 default routes with higher AD for the backup route on your side, and for the download 2 static routes for your LAN on the SP side with the backup route with higher AD).

HTH,

Mohammed Mahmoud.

[mahmoodmkl]

Hi

Thanks for the reply.Actually i tried this.but didnt get any sucess.There is no routing protocol.

Thanks

Mahmood

[mohammedmahmoud · Accepted solution]

Hi Mahmood,

Most of our customers (i work for a service provider) use this solution and they face no problems, try pointing the static routes to both the outgoing interface and the next-hop simultaneously (to make sure that the primary route is removed from the routing table just when the primary interface fails):

ip route 0.0.0.0 0.0.0.0 serial0/0.1 x.x.x.x

HTH,

Mohammed Mahmoud.

[sachin]

HI Mahmood,

This is not as simple as just putting the static route to both the outgoing interface, it will work only when you have both the connection from same ISP, normally nobody takes connection from same ISP.

If you have connection frm two different ISPs your browsing from LAN will work with above solution, when any of ISP is down . But none of your internal servers will be reachable if public IPs are of those ISP of which link is down.Because normally ISPs dont route for each others Public IP.

If you want both ISP should route for your public IP block then you should use BGP.

Regards.

Sachin

[mahmoodmkl]

Hi Mahmood,

Thanks for u r reply.Its working now.

I have two links from the same ISP.

Thanks sachin for u r reply.

Thanks

Mahmood